Prognostic relevance of proliferation-related miRNAs in pancreatic neuroendocrine neoplasms

OBJECTIVE

Pancreatic neuroendocrine neoplasms (PanNENs) are rare tumors arising from the endocrine pancreas; however, their prognosis differs significantly upon their proliferative state, which is characterized by histopathological grading. MiRNAs are small, noncoding RNAs posttranscriptionally regulating gene expression. Our aim was to identify miRNAs with altered expression upon proliferation which can be used as prognostic biomarkers in PanNENs.

METHODS

MiRNA expression profiles of 40 PanNENs were downloaded from Gene Expression Omnibus and were reanalyzed upon tumor grades (discovery cohort). Results of the reanalysis were confirmed by qRT-PCR analysis of five miRNAs on an independent validation cohort of 63 primary PanNEN samples. Cox proportional hazards survival regression models were fit for both univariate and multivariate analysis to determine the miRNAs’ effect on progression-free and overall survival.

RESULTS

Nineteen miRNAs displayed differential expression between tumor grades. The altered expression of three out of five chosen miRNAs was successfully validated; hsa-miR-21, hsa-miR-10a and hsa-miR-106b were upregulated in more proliferative PanNENs compared to Grade 1 tumors. In univariate analysis, higher expression of tissue hsa-miR-21, hsa-miR-10a and hsa-miR-106b of primary PanNENs predicted worse progression-free and overall survival; however, multivariate analysis only confirmed the expression of hsa-miR-21 as an independent prognostic factor.

CONCLUSIONS

The expression of hsa-miR-106b, hsa-miR-10a and especially hsa-miR-21 has prognostic relevance regarding progression-free and overall survival in patients with PanNENs.

Novel insights into the polycythemia-paraganglioma-somatostatinoma syndrome

Worldwide, the syndromes of paraganglioma (PGL), somatostatinoma (SOM) and early childhood polycythemia are described in only a few patients with somatic mutations in the hypoxia-inducible factor 2 alpha (HIF2A). This study provides detailed information about the clinical aspects and course of 7 patients with this syndrome and brings into perspective these experiences with the pertinent literature. Six females and one male presented at a median age of 28 years (range 11-46). Two were found to have HIF2A somatic mosaicism. No relatives were affected. All patients were diagnosed with polycythemia before age 8 and before PGL/SOM developed. PGLs were found at a median age of 17 years (range 8-38) and SOMs at 29 years (range 22-38). PGLs were multiple, recurrent and metastatic in 100, 100 and 29% of all cases, and SOMs in 40, 40 and 60%, respectively. All PGLs were primarily norepinephrine-producing. All patients had abnormal ophthalmologic findings and those with SOMs had gallbladder disease. Computed tomography (CT) and magnetic resonance imaging revealed cystic lesions at multiple sites and hemangiomas in 4 patients (57%), previously thought to be pathognomonic for von Hippel-Lindau disease. The most accurate radiopharmaceutical to detect PGL appeared to be [¹⁸F]-fluorodihydroxyphenylalanine ([¹⁸F]-FDOPA). Therefore, [¹⁸F]-FDOPA PET/CT, not [⁶⁸Ga]-(DOTA)-[Tyr3]-octreotate ([⁶⁸Ga]-DOTATATE) PET/CT is recommended for tumor localization and aftercare in this syndrome. The long-term prognosis of the syndrome is unknown. However, to date no deaths occurred after 6 years follow-up. Physicians should be aware of this unique syndrome and its diagnostic and therapeutic challenges.

The Coexistence of Somatostatinoma and Gastrointestinal Stromal Tumor in the Duodenum of a Patient with Von Recklinghausen's Disease

We herein describe a case of somatostatinoma coexisting with a gastrointestinal stromal tumor (GIST) in the duodenum of an 81-year-old woman with Von Recklinghausen's disease (VRD) and common bile duct stone who presented with diarrhea of three months in duration. Gastroduodenoscopy revealed an ulcer on the second part of the duodenum. A 2.1-cm enhancing tumor was observed to extend from the ulcer on an abdominal computed tomography scan. Subtotal stomach-preserving pancreaticoduodenectomy revealed a somatostatinoma on the papilla of the vater and duodenal GIST. There have been only eight reports on VRD associated with ampullary somatostatinoma and GIST. An awareness of this possibility in patients with gastrointestinal lesions is necessary for proper treatment and patient management.

Case report: recurrent acute pancreatitis secondary to papillary somatostatinoma--a new association

Acute pancreatitis may rarely be caused by papillary mass lesions such as adenocarcinomas and neuroendocrine tumours. Occasionally these papillary lesions may cause recurrent episodes of acute pancreatitis and patients presenting in this way require further pancreatic investigation. We believe this to be the first reported case of a duodenal papillary somatostatinoma causing recurrent acute pancreatitis. The patient was investigated with multiple imaging modalities, both at endoscopy and with more traditional radiology, and treated with resection by Whipple's pancreaticoduodenectomy. If diagnosed early in the absence of distant metastases the prognosis of papillary somatostatinoma with tumour resection is excellent.

Severely fluctuating blood glucose levels associated with a somatostatin-producing ovarian neuroendocrine tumor

CONTEXT

Somatostatin-producing tumors are a rare type of neuroendocrine tumor. Their effects on blood glucose levels have been variously reported, and detailed reports have been scarce.

OBJECTIVE

The aim of this study was to identify the reasons for the extraordinary blood glucose fluctuations in a case with no previous history of diabetes.

PATIENTS AND METHODS

A 68-yr-old nondiabetic woman with an ovarian tumor was suffering from hyper- and hypoglycemia. Based on the results of an oral glucose tolerance test and continuous glucose monitoring, we speculated that the fluctuating blood glucose level was accompanied not only by a low insulin level but also by low counter-regulatory hormones levels, and that those broad hormonal suppressions were caused by a high somatostatin level produced in the ovarian tumor. We performed an oophorectomy and assessed the pathology of the tumor and changes in the blood glucose profile as well as hormonal levels postoperatively.

RESULTS

The blood glucose level was completely normalized after the oophorectomy. Insulin secretion was also normalized. Histological examination showed that the tumor comprised a mature cystic teratoma and a stromal carcinoid. Immunohistochemically, the stromal carcinoid component was positive for somatostatin. The somatostatin level was 8505 pmol/liter preoperatively, which dropped down to 71.5 pmol/liter postoperatively. We found two previous reports of somatostatin-producing ovarian neuroendocrine tumors. Somatostatin levels among cases of ovarian origin were much higher than those among cases of gastrointestinal origins, and cases of ovarian origin all experienced blood glucose fluctuations.

CONCLUSION

Extremely high somatostatin levels and blood glucose fluctuations may be characteristics of somatostatin-producing ovarian neuroendocrine tumors.

Duodenal somatostatinoma: a case report and review

Somatostatinomas are rare functioning carcinoid tumors that usually arise in the pancreas and duodenum. They are seldom associated with typical clinical symptoms; their diagnosis is confirmed only by histological and immunohistochemical studies and the presence of specific hormones. Two distinct clinicopathological forms of somatostatinoma exist: duodenal and pancreatic somatostatinomas. Clinically, compared to pancreatic somatostatinomas, duodenal somatostatinomas are more often associated with nonspecific symptoms and neurofibromatosis, but less often with somatostatinoma syndrome or metastasis. Histologically, duodenal somatostatinomas frequently have psammoma bodies in the tumor cells. We report a case of duodenal somatostatinoma in 58-year-old man with vague epigastric pain and nausea. He did not have diabetes, steatorrhea, or cholelithiasis. Abdominal computed tomography showed a 25-mm mass in the duodenum and 25-mm nodule in the liver. Endoscopic retrograde cholangiopancreatography showed a duodenal submucosal tumor. Although the endoscopic biopsies were free of malignancy, the patient subsequently underwent Whipple's operation for the duodenal mass. Examination revealed as a somatostatinoma using a special stain for somatostatin.

Vasculopathic changes, a somatostatin-producing neuroendocrine carcinoma and a jejunal gastrointestinal stromal tumor in a patient with type 1 neurofibromatosis

A 36-year-old male with neurofibromatosis type 1 (NF-1) presented with symptoms of obstructive jaundice. Imaging showed a periampullary mass, which on endoscopic retrograde cholangiopancreatography biopsy proved to be a somatostatinoma. A Whipple's procedure was performed and a somatostatinoma of the duodenum was confirmed. In addition, the patient had a gastrointestinal stromal tumor (GIST) of the jejunum with accompanying hyperplasia of interstitial cells of Cajal. The somatostatinoma was histologically characteristic with pseudoglandular and solid patterns together with psammoma bodies and lymphovascular invasion. The GIST did not display mutations in c-kit or platelet-derived growth factor receptor genes. The novel finding in this case was the presence of several vessels in the submucosa and muscularis propria of the duodenum displaying prominent intimal hyperplasia and in keeping with so-called neurofibromatosis-associated vasculopathy. These abnormal vessels were within and close to the somatostatinoma only and were not found away from the tumor. It is thought that the vasculopathy is related to NF-1 with abnormal neurofibromin possibly playing a role.

Large somatostatin-producing endocrine carcinoma of the ampulla of vater in association with GIST in a patient with von Recklinghausen's disease. Case report and review of the literature

CONTEXT

Somatostatin-producing endocrine tumors of the duodenum are very rare neoplasms of the gastrointestinal tract. These tumors may be associated with von Recklinghausen's disease.

CASE REPORT

We present the case of a 49-year-old female patient with von Recklinghausen's disease and an incidentally diagnosed ampullary neoplasm. The patient was treated with a classical pancreaticoduodenectomy. At surgery, a mass was found in the greater curve of the stomach which was resected using the classic Whipple procedure. Histology and immunohistochemistry showed that the duodenal tumor was an ampullary somatostatin-producing endocrine carcinoma while the gastric tumor was a gastrointestinal stromal tumor (GIST). The postoperative course was uneventful and the patient is alive, without tumor recurrence, six years after surgery.

CONCLUSION

Somatostatin-producing endocrine tumors of the duodenum are rare tumors, often associated with von Recklinghausen's disease; these neoplasms should be treated aggressively using radical surgical resection. Although local resection may be appropriate for small duodenal somatostatin-producing tumors, a pancreaticoduodenectomy is usually required for larger tumors.

Diagnostic usefulness of FDG-PET for malignant somatostatinoma of the pancreas

A 24-year-old female complaining of diarrhea and back pain was admitted to hospital where a tumor of the pancreatic head was revealed on a computed tomography (CT) scan. Abdominal ultrasonography, CT and celiac angiography revealed a hypervascular lesion on the pancreas. An endocrine tumor, particularly a somatostatinoma, was suspected and hormone levels in the blood were examined. Serum hormone levels were normal, so FDG-PET was performed. An abnormally high accumulation of FDG was detected on the FDG-PET image at the head of the pancreas, and the SUV of the lesion was 3.2, so the mass was considered to be malignant on FDG-PET. Pylorus-preserving pancreatoduodenectomy was performed with a preoperative diagnosis of malignant endocrine tumor. The resected specimen revealed a massive, yellowish-white tumor of the pancreas head measuring 50x 45x38mm. Histologically, the tumor was a malignant islet-cell tumor, and immunohistochemically the tumor stained with an anti-somatostatin antibody, but not with antibodies against glucagons, insulin or vasoactive intestinal polypeptide. The patient was discharged after the operation and has remained well without recurrence for 5 years. Liver metastatic tumors, however, appeared 6 years after the operation.

Somatostatin-producing neuroendocrine tumors of the duodenum and pancreas: incidence, types, biological behavior, association with inherited syndromes, and functional activity

Somatostatin-producing neuroendocrine tumors (SOM-NETs) of the duodenum and pancreas appear to be heterogeneous. To determine their clinicopathological profiles, respective data were analyzed on a series of 82 duodenal and 541 pancreatic NETs. In addition, the clinical records of 821 patients with duodenal or pancreatic NETs were reviewed for evidence of a somatostatinoma syndrome. Predominant or exclusive expression of somatostatin was found in 21 (26%) duodenal and 21 (4%) pancreatic NETs. They were classified as sporadic (n=31) or neurofibromatosis type 1 (NF1)-associated duodenal NETs (n=3), gangliocytic paragangliomas (GCPGs; n=6), or poorly differentiated neuroendocrine carcinomas (pdNECs; n=2). In addition, five duodenal and four pancreatic SOM-NETs were found in five patients with multiple endocrine neoplasia type 1 (MEN1). Metastases occurred in 13 (43%) patients with sporadic or NF1-associated SOM-NETs, but in none of the duodenal or pancreatic MEN1-associated SOM-NETs or GCPGs. Sporadic advanced (stage IV) SOM-NETs were more commonly detected in the pancreas than in the duodenum. None of the patients (including the 821 patients for whom only the clinical records were reviewed) fulfilled the criteria of a somatostatinoma syndrome. Our data show that somatostatin expression is not only seen in sporadic NETs but may also occur in GCPGs, pdNECs, and hereditary NETs. Surgical treatment is effective in most duodenal and many pancreatic SOM-NETs. MEN1-associated SOM-NETs and GCPGs follow a benign course, while somatostatin-producing pdNECs are aggressive neoplasms. The occurrence of the so-called somatostatinoma syndrome appears to be extremely uncommon.

Ampullary somatostatinomas and jejunal gastrointestinal stromal tumor in a patient with Von Recklinghausen’s disease

Von Recklinghausen’s disease is an autosomal dominant hereditary disease associated with a wide number of neoplasms. We report a case of a 47-year-old Caucasian male affected by Von Recklinghausen’s disease who developed a malignant somatostatinoma of the papilla major and minor associated with jejunal gastrointestinal stromal tumour with uncertain behaviour. At laparotomy, multiple hepatic metastases were evident. Whipple pancreaticoduodenectomy, jejunal resection, extensive lymphadenectomy and multiple hepatic wedge resections were performed. The patient was alive without recurrence after 24 mo. This is the fourth case reported in the world literature of a patient with Von Recklinghausen’s disease associated with periampullary somatostatinomas and jejunal stromal tumor. In patients with Von Recklinghausen’s disease who complain of gastrointestinal symptoms, a high suspicion index for periampullary endocrine tumours and/or gastrointestinal stromal tumour is required. An aggressive surgical approach seems to give long term survival also in metastatic patients.

[A case of pancreatic somatostatinoma]

Somatostatinoma is a rare neoplasm usually arising from the pancreas and duodenum which typically presents with indolent, nonspecific symptoms in the absence of systemic neuroendocrine manifestations that characterize somatostatinoma syndrome. It accounts for less than 1% of all gastrointestinal endocrine tumors with an annual incidence of 1 per 40 million. It is often associated with regional and/or portal metastasis at the time of diagnosis, and complete tumor resection is possible only in 60% to 70% of cases. We experienced a case of pancreatic somatostatinoma recently. A 51-year-old woman presented with right upper quadrant abdominal pain and loose stool for one month. A hypermetabolic lesion in the pancreatic head was detected on positron emission tomography-CT (PET-CT) scan. The tumor was resected by pylorus preserving pancreaticoduodenectomy. Immunohistochemical staining of the tumor tissue exhibited diffuse positivity for somatostatin, but was negative for insulin and glucagon. Herein, we report a case of pancreatic somatostatinoma diagnosed postoperatively.

Spectrum of malignant somatostatin-producing neuroendocrine tumors

OBJECTIVE

To evaluate the clinical manifestations and outcome of patients with somatostatinomas--rare neuroendocrine tumors of pancreaticoduodenal origin.

METHODS

We searched the medical archives and tumor registry of our institution for somatostatinomas or somatostatin-staining tumors for the 12-year period from January 1990 to February 2002. In addition, we reviewed laboratory databases for patients who had an elevated serum somatostatin level. Patients with a neuroendocrine tumor and an elevated serum somatostatin level or somatostatin-positive tumor immunostaining were included in this study.

RESULTS

Eleven patients qualified (9 men and 2 women; median age at diagnosis, 45 years; age range, 22 to 73). The diagnosis of a somatostatinoma was made by immunostaining of the tumor in 9 patients and by finding elevated serum somatostatin levels in 2. Five primary tumors were of duodenal and 6 of pancreatic origin. Psammoma body formation and association with neurofibromatosis were seen only in the duodenal tumors. The known primary tumor sizes varied from 2 to 6 cm. Liver metastatic lesions were present in 6 patients, abdominal lymph node involvement was found in 10 patients, and lung, spleen, and ovarian metastatic involvement was noted in 1 patient each. Diabetes was present in 4 patients (36%) and cholelithiasis in 7 (64%). The presence of a mass led to the diagnosis in most patients with primary duodenal tumors, whereas patients with pancreatic tumors were more likely to have endocrine manifestations. A Whipple procedure was performed in 6 patients, distal pancreatectomy in 3, hepatic artery embolization or ligation in 3, and partial hepatectomy in 1. Cancer-related death occurred in 4 patients, 1 to 8 years after diagnosis (median, 4.5 years). At last follow-up, 2 patients were alive without evidence of disease (8 and 10 years after diagnosis), and 3 were alive with liver metastatic lesions. The status of 2 patients was unclear.

CONCLUSION

Somatostatinomas occurred with approximately equal frequency in the duodenum and the pancreas. The duodenal tumors were more likely to be pure somatostatinomas and have psammoma bodies. Pancreatic tumors were more likely to be multihormonal. Cholelithiasis and diabetes were seen in 64% and 36%, respectively, of the patients. Mass effect of the tumor was the usual manifestation leading to diagnosis. These tumors are slow growing, and long-term survival is possible.

Incidental small ampullary somatostatinoma treated with ampullectomy 2 years after diagnosis

Somatostatinomas are rare tumors; ampullary somatostatinomas are very rare. We report a case of a small pure somatostatin-producing neuroendocrine tumor of ampulla of Vater in a 54-year-old woman with neither neurofibromatosis nor somatostatinoma syndrome, "incidentally" discovered during an abdominal computed tomography. The patient initially refused other adjunctive exams but after 2 years she was admitted, presenting with itch, night sweats, severe fatigue, and unintentional weight loss. The size of the tumor (1.5 cm) and the other radiologic findings had not changed since the abdominal CT scan 2 years before. The somatostatin, gastrin, glucagons, serotonin, vasoactive intestinal peptide, dopamine, norepinephrine, epinephrine, and calcitonin plasma levels were normal. ERCP-obtained biopsies revealed a neuroendocrine tumor with psammoma bodies; immunohistochemical profile was positive for chromogranin and somatostatin. The patient underwent surgery; intraoperative histologic examination of lymph nodes sampling of perihepatic and periduodenal lymph nodes was negative for metastasis. We performed, therefore, a transduodenal ampullectomy. The patient continues to do well at 3 years' follow-up with no evidence of local or distance recurrence of disease.

Somatostatinoma: collision with neurofibroma and ultrastructural features

The clinical presentation, histopathology and immunoelectron microscopic features of two cases of duodenal somatostatinoma are described, one of which is a hitherto unreported example of a collision tumour with a neurofibroma. Ultrastructural morphometric immunoelectron microscopy studies revealed the presence of four types of cells in both tumours, but there was no difference in the proportions of these cells between the collision tumour and the non-collision tumour. Neurosecretory granules ranging in size from 255-815 nm were generally larger than those previously reported for somatostatinomas and somatostatin was identified in granules of all sizes across this range. Neither tumour was associated with the somatostatinoma syndrome comprising associated diabetes mellitis, steatorrhoea and cholelithiasis.

Characterization of the functional and growth properties of long-term cell cultures established from a human somatostatinoma

In somatostatinoma, a rare malignant somatostatin (SST)-secreting neoplasia, tumour regression is rarely observed, implying the need for novel antiproliferative strategies. Here, we characterized a long-term culture (SST-secreting cancer (SS-C cells)) established from a human somatostatinoma. High concentrations of SST and chromogranin A were released by SS-C cells and SST release was stimulated by depolarizing stimuli and inhibited by the SST analogue, octreotide. SS-C cells expressed mRNA for SST receptor (SSTR) subtypes 1, 2 and 4, being also able to bind native SST. Moreover, SS-C cells were positively stained with an antibody to SSTR2. SS-C cells also expressed interferon-gamma (IFN-gamma) receptor mRNA and measurable telomerase activity. Our findings indicate that in vitro exposure of SS-C cells to native SST-28, to octreotide, to IFN-gamma, or to 3'-azido-3'deoxythymidine (AZT), a telomerase inhibitor, results in inhibition of SS-C cell proliferation. Concomitant with growth inhibition, apoptosis was detected in SST-, octreotide-, IFN-gamma- or AZT-treated SS-C cell cultures. Taken together our results characterized native SST, SST analogues, IFN-gamma and a telomerase inhibitor as growth-inhibiting and proapoptotic stimuli in cultured human somatostatinoma cells. Based on these findings, the potential of SST analogues, IFN-gamma and AZT, alone or in combination, should be further explored in the medical treatment of somatostatinoma.

Duodenal somatostatinoma associated with diabetic ketoacidosis presumably caused by somatostatin-28 hypersecretion

CONTEXT

Extrapancreatic somatostatinoma is very rare and clinically distinguished from its pancreatic counterpart because somatostatinoma syndrome with mild diabetes is rare in extrapancreatic somatostatinoma because of poor secretion of somatostatin. Moreover, because somatostatin inhibits the secretion of insulin and glucagon simultaneously, true diabetic ketoacidosis (DKA) seldom ensues.

PATIENT

A 23-yr-old woman presented with DKA and an abdominal mass. A computed tomography scan showed a huge, encapsulated mass in a duodenal submucous portion. A high circulating level of somatostatin was detected (67.2 pmol/liter; reference range, 0.6-7.3 pmol/liter).

INTERVENTION

The tumor mass was successfully removed with Whipple's procedure, and the patient gradually recovered both clinically and biochemically.

RESULTS

Immunohistochemical staining of the tumor tissue exhibited diffusely positive for somatostatin and somatostatin-28 but negative for insulin, glucagon, calcitonin, serotonin, and S-100.

CONCLUSION

As far as we know, this is the first case report of gastrointestinal somatostatinoma associated with DKA.

Endocrine tumours of the pancreas

Endocrine pancreatic tumours (EPTs) are uncommon tumours occurring in approximately 1 in 100,000 of the population, representing 1-2% of all pancreatic neoplasms. Some of the tumours may be part of multiple endocrine neoplasia type one (MEN-1) syndrome or von Hippel-Lindau (vHL) disease. EPTs are classified as functioning or non-functioning tumours on the basis of their clinical manifestation. The biochemical diagnosis of EPT is based on hormones and amines released. Besides specific markers such as insulin, there are also general tumour markers such as chromogranin A, which is the most valuable marker and has been reported to be increased in plasma in 50-80% of patients with EPTs and correlates with tumour burden. The location of endocrine tumours of the pancreas includes different techniques, from endoscopic investigations to scintigraphy (e.g. somatostatin receptor scintigraphy) and positron emission tomography. The medical treatment of endocrine pancreatic tumours consists of chemotherapy, somatostatin analogues and alpha-interferon. None of these can cure a patient with malignant disease. In future, therapy will be custom-made and based on current knowledge of tumour biology and molecular genetics.

Rare endocrine tumours of the GI tract

Functional pancreatic endocrine tumors other than gastrinoma and insulinoma are quite rare. The principles of management include the diagnosis and management of the functional hormonal syndrome, and management of the potentially malignant tumor. Optimally, control of the hormonal syndrome is achieved preoperatively to stabilize the patient status for the operation, however, resection may be an important part of the control of the hormonal syndrome. Ultimately, the only curative treatment for these neoplasms is complete tumour resection, when feasible.

Epidemiology, tumour biology and histopathological classification of neuroendocrine tumours of the gastrointestinal tract

The diffuse neuroendocrine cell gives rise to a heterogeneous population of tumours which differ in their morphological and functional features. The term 'carcinoid', although well established in medical terminology, is therefore no longer adequate to cover the entire spectrum of neuroendocrine neoplasms. Here we use the term neuroendocrine tumours (NET), which was suggested in the WHO classification of 2000, and review the most important NET entities that are currently recognised in the gastrointestinal tract, highlighting their distinguishing features.

Metastatic somatostatinoma of the chest wall

A 72-year-old male was diagnosed as having a thoracic tumor in the left chest wall five years after resection of primary pancreatic somatostatinoma. The tumor was suggestive of metastasis to the chest wall or to the left lung from the previously resected somatostatinoma based on the abnormally elevated serum somatostatin level. Percutaneous biopsy confirmed that the lesion was an islet cell tumor and thoracotomy demonstrated metastasis to the left third rib without involvement of the left lung. Our case represents a rare documentation of somatostatinoma metastatic to the chest wall for which complete resection was performed.

Duodenal somatostatinoma: clinical and immunohistochemical patterns--difficult differential diagnosis in regard to gangliocytic paraganglioma: report of a case

The authors report a large duodenal somatostatinoma, a very rare tumor entity. A 8.5 cm globular mass in the area of the unicate process of the pancreas was detected in a 45 year old caucasian female by computerized tomography. The patient had only mild complaints. Initial treatment consisted of right pancreatectomy with preservation of the pylorus. Histological evaluation rendered a diagnosis of low-grade malignant neuroendocrine carcinoma with expression of somatostatin, respectively of somatostatinoma arising in the duodenum and infiltrating into the pancreas. 26 months after the initial surgery liver and lymph node metastases were detected and surgically removed. This case confirms that duodenal somatostatinomas are very difficult to diagnose preoperatively because of unspecific symptoms. Most duodenal somatostatinomas are found incidentally. Treatment of choice is radical surgical resection with a possible cure in early stages of the disease. Even a large tumor as ours is resectable with negative surgical margins. Management of recurrent or metastatic disease is also surgical. Additional chemotherapy and supportive care may be beneficial for the patient.

Concurrent gastrinoma and somatostatinoma in a 10-year-old Portuguese water dog

Severe hypergastrinaemia in the dog is considered a strong indicator for a gastrin-producing pancreatic islet cell tumour. In human medicine, gastrinomas are described as enteropancreatic neuroendocrine tumours that cause the Zollinger-Ellison syndrome. However, in contrast to the supposed origin of canine gastrinomas in pancreatic islets, gastrinomas in human beings arise predominantly in the duodenum and gastric antrum, and are often a component of the syndrome of multiple endocrine neoplasia type I. This report is of a canine case of multiple endocrine neoplasms, consisting of a pancreatic islet cell somatostatinoma, and a gastrinoma in the mesenteric lymph nodes and liver. From the literature and the authors' findings, it is concluded that the clinical diagnosis of hypergastrinaemia is not pathognomonic for a gastrin-producing islet cell tumour. Furthermore, the presence of an islet cell tumour in the face of hypergastrinaemia does not warrant a diagnosis of an islet cell gastrinoma. Immunohistochemistry is necessary to confirm the diagnosis of a pancreatic islet cell gastrinoma.

Malignant duodenal somatostatinoma presenting in association with von Recklinghausen disease

Somatostatinomas are extremely rare periampullary malignant neuroendocrine tumors that may be associated with von Recklinghausen disease or type-I neurofibromatosis. Duodenal somatostatinomas are distinguished from pancreatic somatostatinomas by their frequent association with type-I neurofibromatosis and typically absence of somatostatinoma syndrome. We report a very rare and atypical case of malignant duodenal somatostatinoma presenting with somatostatinoma syndrome in association with type-I neurofibromatosis.

A small, incidentally detected pancreatic somatostatinoma: report of a case

We report an asymptomatic 72-year-old woman with a small, incidentally detected, pancreatic somatostatinoma. The tumor, measuring 1 cm in diameter, showed a hypervascular pattern of contrast enhancement on computed tomography, and was found angiographically to receive a blood supply from the posterior superior pancreaticoduodenal artery. The results of preoperative hormonal assays all were normal. No assay for somatostatin was performed. No abnormality in either the pituitary or parathyroid was found. We thus considered the tumor to be a sporadic, nonfunctioning endocrine cell tumor, and enucleation was carried out. As some tumor cells in the resected specimen showed immunoreactivity for somatostatin, a diagnosis of somatostatinoma was made. Therefore, the possibility of somatostatinoma should be kept in mind when making a differential diagnosis of pancreatic endocrine tumors in cases where even a small hypervascular tumor is detected on enhanced computed tomography.

Atypical thymic carcinoid and malignant somatostatinoma in type I multiple endocrine neoplasia syndrome: case report

Thymic carcinoid and malignant somatostatinoma are both rare, and their concurrent presence in multiple endocrine neoplasia type 1 (MEN-1) has never been reported in the English literature to date. We present a patient with thymic carcinoid and malignant somatostatinoma in association with MEN-1. The patient eventually died of pulmonary aspergillosis and respiratory failure. Autopsy showed a 16 x 10 x 8-cm thymic carcinoid tumor, parathyroid and adrenal gland hyperplasia, and malignant somatostatinoma of the pancreas with a metastatic tumor over the splenic hilum.

Somatostatinoma of the papilla of Vater with multiple gastrointestinal stromal tumors in a patient with von Recklinghausen's disease

We report a case of somatostatinoma of the papilla of Vater with multiple gastrointestinal stromal tumors in a patient with von Recklinghausen's disease (VRD). A 64-year-old woman who had had recurrent attacks of acute pancreatitis and cholangitis was found, on gastroduodenal endoscopy, to have a tumor of the papilla of Vater and multiple submucosal tumors of the stomach and duodenum. Numerous submucosal tumors were observed in the stomach, duodenum, and jejunum, and total excision of the papilla of Vater and resection of the duodenal and jejunal submucosal tumors was performed. The tumor of the papilla of Vater showed the histologic appearance of a dense proliferation of tumor cells in acinar form, from the duodenal mucosa to the muscle layer, and psammoma bodies were revealed within the tumor. Immunohistologically, the tumor cells were intensely positive for somatostatin. The submucosal tumors of the duodenum and jejunum were negative for smooth muscle actin, s-100, and neuron-specific enolase (NSE), and positive for CD34 and c-kit, and they were diagnosed as gastrointestinal stromal tumors (GISTs) according to the strict definition. The only 25 cases of papilla of Vater somatostatinoma associated with VRD to have been reported in the English-language literature since 1982 are reviewed, as well as our own case.

Case report: somatostatin producing teratoma, causing rapidly alternating extreme hyperglycemia and hypoglycemia, and ovarian somatostatinoma

A 54-year-old woman presented with extremely fluctuating and symptomatic blood glucose levels. Very high levels of somatostatin and low levels of insulin, C-peptide, gastric inhibitory peptide (GIP), and glucagon-like peptide-1 (GLP-1) in peripheral blood were constantly present. A benign somatostatinoma was localized by meta-iodobenzyl guanidine iodine 123 (MIBG-I(123)) scintigraphy and successfully removed encapsulated in an ovarian teratoma. The patient made a complete recovery. The case described is unique with regard to clinical symptomatology and anatomic localization of the tumor.

[Von Recklinghausen's disease associated with pancreatic somatostatinoma]

INTRODUCTION

Pancreatic somatostatinoma is a rare entity and its association with Von Recklinghausen's disease has only been described on two occasions. We report a new observation, with clinical and evolving status differing from those described in isolated cases of somatostatinoma.

OBSERVATION

A 28 year-old man presenting with familial Von Recklinghausen's disease, had suffered for 10 years from paroxysmic abdominal pain. He was hospitalized for intense pain. Imaging revealed a retroperineal tumoral formation. Following duodenopancreatectomy, somatostatinoma was diagnosed. Diffuse metastatic miliary was revealed and multiple glandular metastases.

DISCUSSION

Other than the rarity of the morbid association (pancreatic somatostatinoma and Von Recklinghausen's disease) described, this case is particular in that the patient was very young, symptomatology was unapparent and tumoral evolution was minimal.

Duodenal somatostatinoma of the ampulla of vater diagnosed by endoscopic fine needle aspiration biopsy: a case report

BACKGROUND

Duodenal somatostatinoma is a rare neuroendocrine neoplasm. A better prognosis can be obtained if these tumors are resected at an early clinical stage. Endoscopic punch biopsy has been the method most commonly used for the preoperative diagnosis of neuroendocrine duodenal tumors. To the best of our knowledge, endoscopic fine needle aspiration biopsy (FNAB) of duodenal somatostatinoma has not been reported before.

CASE

A 41-year-old, black female presented with upper gastrointestinal bleeding as well as elevated bilirubin, liver enzymes and glucose. Computed tomography, esophagogastroduodenoscopy and endoscopic retrograde cholangiopancreatography (ERCP) detected a mass at the region of the ampulla of Vater partially obstructing the pancreatic duct. The initial punch biopsy yielded only intestinal mucosa. Subsequent endoscopic FNAB suggested the diagnosis of a neuroendocrine neoplasm, as confirmed by additional punch biopsies. Immunohistochemical and electron microscopic studies disclosed somatostatin production by the tumor, which was resected through a modified Whipple procedure. The patient recovered fully.

CONCLUSION

This case demonstrates the usefulness of endoscopic FNAB in diagnosing submucosal gastrointestinal neuroendocrine tumors.

[Duodenal somatostatinoma. Anatomic/clinical study of 12 operated cases]

STUDY AIM

Duodenal somatostatinomas (DS) are very rare neuro-endocrine tumours. The aim of this retrospective and multicentric study was to report the clinical and pathological characteristics of these neoplasms in a series of 12 patients and to compare them with the literature.

PATIENTS AND METHODS

From 1987 to 1998, 12 patients were operated for a DS. There were seven women and five men ranging in age from 23 to 72 years (mean age: 56.6 years). Four patients had an associated von Recklinghausen's disease, one of them with multiple endocrine neoplasia (MEN type IIa) and medullary carcinoma of the thyroíd. The surgical procedures were pancreaticoduodenectomy (n = 8), small bowel resection (n = 2), inferior gastrectomy (n = 1) and gastrojejunostomy with hepatic metastases biopsies (n = 1). The tumour was mainly located on the 2nd duodenum (n = 10), with a mean size of 2.7 cm (ranging from 0.4 to 6 cm) and with a pancreatic invasion in three patients. A metastatic disease was present at the time of diagnosis in eight patients. There were, according to Capella's classification, two patients in the groups I and II, and ten patients in group III (83%), respectively.

RESULTS

There was one postoperative death after a pancreaticoduodenectomy. Three patients secondarily died from tumoral progression. Eight patients were alive, with a mean follow-up of 84 months (ranging from 5 to 290 months), at the end-point of the study.

CONCLUSION

Duodenal somatostatinomas are rare neuroendocrine, generally non-functioning, well-differentiated tumours with a low grade of malignancy. The association with the von Recklinghausen's disease is frequent. The clinical somatostatinoma syndrome with diabetes, diarrhea and biliary lithiasis is rare. The treatment is surgical even with a metastatic disease. The 5-year survival rate is better than those of the pancreatic somatostatinomas or the duodenal gastrinomas.

[Duodenal somatostatinomas associated with von Recklinghausen's neurofibromatosis. Apropos of 2 cases]

Somatostatinomas are rare neuroendocrine tumors; they are essentially located in the pancreas and in the duodenum. The association with a neurofibromatosis type I is especially observed when the tumor is located in the ampulla of Vater. These tumors are not associated with a "somatostatin syndrome", but often present with gastrointestinal bleeding, abdominal pain and obstructive jaundice. The diagnosis is confirmed by immunohistochemical studies. The aim of this study is to report 2 cases of metastazing duodenal periampullary somatostatinomas associated with von Recklinghausen's disease and to discuss the prognosis of these tumors. Future genetic research are necessary as point out the familial feature of this association in one of our cases.

Chromosomal alterations in human pancreatic endocrine tumors

Comparative genomic hybridization (CGH) was used to investigate changes in DNA copy numbers in 25 paraffin-embedded samples of pancreatic endocrine tumors from 23 patients. Insulin was the dominant hormone in 12, glucagon in 7, somatostatin in 1, and pancreatic polypeptide in 2 tumors. One to 15 (mean, 8.1) changes in DNA copy numbers were observed in 22 of the 25 tumors. The most recurrent aberration, found in 68% of the tumors, involved gains in chromosome 7 with a minimal overlapping region at 7q11.2. Other frequent gains included chromosomes 19 (60%) and 14 (56%). Chromosome arm 20q was amplified in 48% of the cases with the minimal overlapping region of 20q11.1-13.1. The two most frequent DNA losses were found at 11q21-22 in 32% and at 11p13-15 in 24% of the cases. The amplified chromosomal regions contain several candidate genes that may be involved in islet cell tumorigenesis. The regions with most frequent losses are likely to contain still uncharacterized tumor suppressor genes. Wiley-Liss, Inc.

Endoscopic ultrasound is highly accurate and directs management in patients with neuroendocrine tumors of the pancreas

Preoperative localization of pancreatic neuroendocrine tumors with traditional imaging fails in 40-60% of patients. Endoscopic ultrasound (EUS) is highly sensitive in the detection of these tumors. Previous reports included relatively few patients or required the collaboration of multiple centers. We report the results of EUS evaluation of 82 patients with pancreatic neuroendocrine tumors.

METHODS

We prospectively used EUS early in the diagnostic evaluation of patients with biochemical or clinical evidence of neuroendocrine tumors. Patients had surgical confirmation of tumor localization or clinical follow-up of >1 yr.

RESULTS

Eighty-two patients underwent 91 examinations (cases). Thirty patients had multiple endocrine neoplasia syndrome type 1. One hundred pancreatic tumors were visualized by EUS in 54 different patients. The remaining 28 patients had no pancreatic tumor or an extrapancreatic tumor. Surgical/pathological confirmation was obtained in 75 patients. The mean tumor diameter was 1.51 cm and 71% of the tumors were < or =2.0 cm in diameter. Of the 54 explorations with surgical confirmation of a pancreatic tumor, EUS correctly localized the tumor in 50 patients (93%). Twenty-nine insulinomas, 18 gastrinomas, as well as one glucagonoma, one carcinoid tumor, and one somatostatinoma were localized. The most common site for tumor localization was the pancreatic head (46 patients). Most tumors were hypoechoic, homogenous, and had distinct margins. EUS of the pancreas was correctly negative in 20 of 21 patients (specificity, 95%). EUS was more accurate than angiography with or without stimulation testing (secretin for gastrinoma, calcium for insulinoma), transcutaneous ultrasound, and CT in those patients undergoing further imaging procedures. EUS was not reliable in localizing extrapancreatic tumors.

CONCLUSIONS

In this series, the largest single center experience reported to date, EUS had an overall sensitivity and accuracy of 93% for pancreatic neuroendocrine tumors. Our results support the use of EUS as a primary diagnostic modality in the evaluation and management of patients with neuroendocrine tumors of the pancreas.

Ampullary somatostatinoma in a patient with Merkel cell carcinoma

A 59-yr-old white man with Merkel cell carcinoma of his right leg status post extensive skin resection and chemotherapy had dilated hepatic and common bile ducts on a routine follow-up abdominal CT scan. A 1.9-cm ampullary mass was appreciated on endoscopy. Histology showed psammoma bodies and positive immunoperoxidase staining consistent with a somatostatinoma. Merkel cell tumors and somatostatinomas are extremely rare neuroendocrine tumors derived from neural crest cells. Associations have been found between somatostatinomas and other islet cell tumors with multiple endocrine neoplasia syndromes, but no reported association has been published between islet cell tumors and Merkel cell tumors. This patient represents the first documented case of Merkel cell carcinoma and somatostatinoma in a single patient. Such an occurrence may represent a previously undescribed neuroendocrine tumor syndrome, and this possibility should be considered when either tumor is diagnosed.

Duodenal somatostatinoma presenting as upper gastrointestinal bleeding

Duodenal somatostatinoma is a rare cause of upper gastrointestinal bleeding. We report the case of a 55-yr-old woman who presented with upper gastrointestinal hemorrhage due to a duodenal somatostatinoma. We discuss the characteristics of these tumors, and review the literature on diagnostic workup and management.

Heterotopic pancreas, periampullary somatostatinoma and type I neurofibromatosis: a pathogenetic proposal

This case documents the association of ectopic pancreatic tissue with a duodenal somatostatinoma in a patient with type I neurofibromatosis. Pancreatic ducts have been noted within the centres of somatostatinomas, but little significance has been attached to this finding. Here we describe a patient in whom a separate proliferation of somatostatin cells occurred in association with the ectopic pancreatic ductular epithelium. This lesion bore a striking resemblance to the ductulo-insular or ductulo-endocrine complexes that are seen in nesidioblastosis in the pancreas. We therefore postulate that the ducts, which are sequestered within somatostatinomas, are of pathogenetic significance. The somatostatin-producing cells arise from these ducts, very much in the fashion of ductulo-endocrine complexes in nesidioblastosis.

Somatostatinoma/inhibitory syndrome: a statistical evaluation of 173 reported cases as compared to other pancreatic endocrinomas

Somatostatin is known to inhibit the secretory release of other peptide hormones. Somatostatinomas associated either with or without somatostatinoma (inhibitory) syndrome are rare neoplasms among gut-pancreatic endocrinomas. Collected from international literature, this study aimed to perform a statistical analysis on 173 patients with somatostatinoma/inhibitory syndrome. The evaluation further attempted to provide investigators in this particular field of research with extensive and precise information on the present situation of somatostatinoma. The 173 patients consisted of 81 with pancreatic somatostatinomas and 92 with extrapancreatic somatostatinomas. Most of the latter were found to have originated in the duodenum and may be termed as carcinoid somatostatinoma. Where data were considered to be adequate, a comparative study was carried out between two groups, pancreatic and duodenal, each consisting of 81 patients. A statistically significant difference between these two groups was found in the incidence of inhibitory syndrome (18.5% versus 2.5%) and von Recklinghausen's disease (1.2% versus 43.2%), large size of tumor (>20 mm) (85.5% versus 41.4%), multisecretory activities (33.3% versus 16.3%), and presence of psammoma bodies (2.5% versus 49.4%). There was no statistically significant difference in the rate of metastases and malignancy between the two groups. The average postoperative 5-year survival rate was 75.2% in 90 patients overall, 59.9% in 44 with metastases and 100.0% in 46 without metastases. Compared with the other pancreatic endocrinomas, including PPomas, glucagonomas, vipomas, gastrinomas, and insulinomas, somatostatinomas were characterized by the low rate of the relevant syndrome and multiple endocrine neoplasia syndrome type 1. There was a low rate of multiplicity, and a high incidence of psammoma bodies in the duodenal group particularly with von Recklinghausen's disease. A high rate of malignancy was recorded, resulting in a low postoperative survival rate of patients with metastases. In conclusion, somatostatinomas exhibited characteristic features quite different from those of the other pancreatic endocrinomas regarding multiple points.

[Duodenal somatostatinomas associated with von Recklinghausen disease]

A case of von Recklinghausen's disease with double somatostatin producing neuroendocrine tumour of the ampulla and duodenum is reported. A search of the world's literature revealed 28 patients with immunohistologically proven duodenal somatostatinoma associated with type I neurofibromatosis. These tumours are seldom associated with a recognizable "somatostatin syndrome", but often present with obstructive jaundice, duodenal obstruction, weight loss or gastrointestinal bleeding. Histologically, psammoma bodies are frequently encountered in the glandular lumina of duodenal somatostatinomas (66%), whereas their presence in other neuroendocrine tumours of the gastrointestinal tract is very rare. Metastatization is rare (27%) and mainly confined to lymph nodes (88%). In the world literature duodenal somatostatinoma is associated with von Recklinghausen's disease in 50%.

Carcinoid somatostatinoma of the duodenum

Carcinoid somatostatinoma is a rare neuroendocrine malignant tumour and the duodenal location is an atypical site of presentation of which only few cases have been reported in the literature. A case of duodenal carcinoid somatostatinoma metastatic to lymph nodes in a 66-year-old patient is presented with an update of the literature. No relevant signs or symptoms were associated to the retrogastric lymph-node mass, which deformed but did not infiltrate the stomach wall. At the first and third portion of the duodenum, two polipoid endoluminal nodules (size 1 cm) were found with adjacent adenopathy partially adherent to the head of the pancreas and with thickening of the antropyloric wall. The patient underwent antrectomy duodenum mobilization and lymphadenectomy in the hepatic artery region. The treatment was successful and, over 3 years after diagnosis, there has been no clinical or radiological evidence of relapse. Duodenal somatostatinoma is rare and its diagnosis is often incidental. Surgery would be the appropriate treatment in the early stage of the disease with good chances of cure.